1. Field of the Invention
The invention relates to a method and apparatus for selectively and securely enabling additional functionality of an electronic component not expressly enabled at the manufacturing or design stages based upon cryptography principles.
2. Description of the Related Art
Cryptography is generally defined as the technology of encoding information so that the information itself, upon storage and/or transmission, can only be accessed by individuals authorized to utilize the information. Cryptography has wide ranging application in various fields and implementations. For example, cryptography can be used to encrypt a sensitive data file, such as a business plan, so that other parties, such as competitors, even if they gain access to the physical location of the data, cannot take advantage of the content of the data. Additionally, cryptography is regularly used to send and receive secure messages between users via e-mail, radio transmission, and satellite communications, along with many other data transmission links. In implementing these types of cryptographic systems, various “types” of cryptography are used. For example, private key cryptography is a type of cryptography where the sender and receiver both have the same key or similar keys, which are used to decode the encrypted message/data. Alternatively, public key cryptography is a form of cryptography in which each user has a public key and a private key, and therefore, messages are sent encrypted with the receiver's public key and the receiver decrypts the messages through use of the private key. Using the public key method, the private key is generally not revealed to anyone other than the intended users and/or recipients of the information. Another form of cryptography is symmetric key cryptography, which is often used in computer transmission related situations, wherein both ends have the same encryption key, which is used for encryption and decryption.
Furthermore, although general cryptography has been a practiced art for nearly 100 years, recent advances in computer related technologies have opened a whole new realm of applications for cryptography. For example, given current computer technology, cryptographic methods are often implemented in various software applications in order to enable and/or disable access to selected software and/or hardware functions. However, software driven cryptographic functions have an inherent degree of vulnerability as a result of their code driven nature.
One particular area where cryptographic methods have been recently used is in the computer hardware enablement field. Although previous implementations such as physical jumpers and secret registers are effective from a physical point of view, these methods are unsecured, and therefore, impractical for most computer applications, as they can easily be bypassed by a clever user. An example of the use of these types of methods is when manufacturers of electronic/computer components manufacture components having various ranges of capabilities and options, as evidenced by the different models of the product. However, in view of the cost associated with producing multiple variations/models of a product in order to create the range of capabilities desired by consumers, manufacturers often produce a single product capable of executing all of the desired functions of the entire product line. This product is then sold as the “top of the line” model. Then, in order to generate the “lower” models, the top of the line model is simply sold with one or more of the features disabled. Therefore, through this technique, manufacturers are generally able to manufacture a single product line having a single design and manufacturing cost, wherein the single product is capable of supporting numerous product models in a product line.
This process has a second advantage, as the manufacturer is then able to offer consumers the option of upgrading their product, without having to physically exchange the hardware for an upgraded model. Rather, the manufacturers can simply enable the desired functions of the hardware in order to upgrade the product. However, this advantage comes with an inherent disadvantage, as a consumer who knows that the product purchased includes disabled upgrades may attempt to enable the additional functionality of the product without the manufacturer's permission, which eliminates or at least reduces the possibility of the manufacturer obtaining compensation for the upgraded product. This situation has been attempted to be addressed through previous functionality enablement methods (jumpers and private registers), however, the vulnerability of these methods has been shown to be nearly ineffective against a reasonably sophisticated attacker.
Therefore, in view of the vulnerability of previous enablement methods in conjunction with the desired manufacturing methods for electronic/computer related products, it is an object of the present invention to implement a cryptographic method wherein the secure portions of the method, e.g. the relevant keys, are implemented in electronic/computer products. Secure, for purposes of cryptographic enablement, is generally defined as the point where the cost of obtaining unauthorized access to a component exceeds the cost associated with obtaining authorized access. More particularly, it is an object of the present invention to implement cryptographic functions for enabling functionality of electronic/computer related components, wherein the relevant secure key related information is contained within computer hardware in a non-volatile memory device and not within a purely software driven configuration. Further still, it is an object of the present invention to provide the ability to conduct secure functionality enablement on electronic/computer related components, wherein a public key for enabling the component is contained onboard and utilized in conjunction with a randomly generated component identifier in order to selectively enable additional functionality of the component.